Re: [PATCH v2] configure: Fix GCC version checking

On Wed, 18 Jul 2018 20:31:46 +0930
Joel Stanley <[email protected]> wrote:

> The case statement fails to match as the braces are stripped when the
> configure.in is converted to the configure script.
> 
> This is bad, as the configure script then decides to set GCC to false,
> and no optimisation flags are applied.

Thanks Joel, with this patch applied I see a huge improvement in 
performance on my POWER9. Some tests are over 5x faster. Not a
surprise when we were previously building without any optimisation
whatsoever.

Tested-by: Anton Blanchard <[email protected]>

Anton

> Signed-off-by: Joel Stanley <[email protected]>
> ---
> v2: The first fix was incorrect, as I was testing the changes
> by hacking configure not configure.in. When generating configure,
> single quotes are removed.
> 
> This has been tested on x86_64 and ppc64le.
> 
>  configure.in | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/configure.in b/configure.in
> index cea313d..aee44a6 100644
> --- a/configure.in
> +++ b/configure.in
> @@ -96,7 +96,7 @@ if test "x${GCC}" = "xyes"; then
>  		AC_MSG_CHECKING(version of GCC)
>  		GCC_version="`${CC} --version | sed -n '1s/^[[^ ]]*
> (.*) //;s/ .*$//;1p'`" case "${GCC_version}" in 
> -		[0-9]*[0-9]*)
> +		[[0-9]]*[[0-9]]*)
>  			AC_MSG_RESULT(${GCC_version})
>  			;;
>  		*)


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